EFFECT OF SUBLETHAL X-IRRADIATION OF GUINEA PIGS ON VACCINALL TULAREMIA INFECTION,

Abstract

Abstract : To delineate differences in the resistance of irradiated and nonirradiated animals to live tularemia vaccine, the chronological appearance and growth rate of LVS in the lung, liver, spleen, and blood of guinea pigs were studied. Nonirradiated controls and guinea pigs having reveived 140 R three days previously were exposed via the respiratory route to 100,000 cells of LVS and sacrificed at intervals from one to 21 days. No major differences were noted in the time of appearance, growth rate, maximum organism content, or time of clearance of LVS from the tissues of irradiated and nonirradiated animals; hence, there was no evidence of a change from a self-limiting to a fulminating type of infection resulting from irradiation of the animals. Also, no appreciable difference in the time of appearance of agglutinins or maximal titer was noted in the two groups of animals. The production of agglutinins in irradiated animals in response to vaccination with LVS is in contrast to the reported inhibition of antibody response in animals inoculated with killed organaganisms or purified antigens subsequent to irradiation.